A general fire-blocking door lock structure is installed on one side of a fire-blocking door, with a frame member horizontally mounted on the center of the fire-blocking door. By pushing a push plate contained within the frame member, a mechanism inside a door lock casing unit is driven to move downwardly, causing a latch to be drawn back to release the locking state of the door lock, thereby opening the door.
Moreover, a door lock transmission mechanism which comprises a handle bar (or a push plate) and/or a lock barrel is installed on the other side of the door. Users can unlatch the fire-blocking door lock to open the door from the other side of the door by pushing the handle bar or the push plate, or inserting a key into the lock barrel. Furthermore, the key inserted into the lock barrel can also lock the fire-blocking door lock, in order to prevent unauthorized people or burglars from entering. The foregoing conventional door lock transmission mechanism has been disclosed in Taiwan Patent No. 486011 and No. 414242.
However, when the fire-blocking door lock according to such patents is locked, an actuating member, such as the handle bar or the push plate, is caught and fixed with inner parts of the door lock transmission mechanism. in other words, when the fire-blocking door lock is locked by a key, the handle bar or the push plate can not be pressed down by users. Therefore, if the handle bar or the push plate is malevolently struck, the inner parts of the door lock transmission mechanism and the assembly structure thereof may be damaged. Accordingly, while such conventional door lock transmission mechanism is locked, the parts of the door lock transmission mechanism and the assembly structure thereof may easily fail to function due to the aforementioned vulnerability.
Meanwhile, because the parts of the conventional door lock transmission mechanism and the assembly structure thereof may be easily damaged, higher maintenance costs and more maintenance time result. Moreover, because of the high failure rate of such door lock transmission mechanism, the operational efficiency of the door lock may be reduced, thereby adversely affecting operation. Therefore, said conventional door lock transmission mechanism is not only disadvantageous in terms of maintenance and operation, but also inclined to influence the normal safety function of the fire-blocking door lock due to the operational problems.
Furthermore, due to the lack of flexibility of the structural design of the foregoing conventional door lock transmission mechanism, said door lock transmission mechanism can only be applied to specific fire-blocking door locks compatible with its design principles. Therefore, the application of the conventional door lock transmission mechanism is restricted to only a few types of fire-blocking door locks, lacking applicability to many types of fire-blocking door locks.
From the foregoing description, because the handle bar or the push plate of said conventional door lock transmission mechanism is easily damaged by excess external force, not only the problems of maintenance, cost, and operation may be induced, but also the effective actuation of the fire-blocking door lock may be obstructed by vulnerable parts of the door lock transmission mechanism, so that users may be endangered. Accordingly, said conventional door lock transmission mechanism has drawbacks, making an alternative design desirable.